A number of medical devices, cardiac pacemakers for example, are intended to deliver or receive an electric current to a patient. However, inadvertent current discharge to a patient or to attending medical personnel is sometimes possible because of exposed or uninsulated electrical connectors or plugs that electrically link the power source to the electrodes contacting the patient. The electrodes themselves may also have uninsulated regions that can touch one another while being implanted into the patient, or due to bad positioning or being moved leading to short circuits, equipment damage and possible patient injury.
Regulatory mandates require that connections, connectors or connector pins on electrical leads that are to be connected to a medical device such as an External Pacer Generator (“EPG”), be shrouded with dielectric material. However, the insulating shrouds placed around connector pins can be incompatible with the corresponding receiving connectors that are installed in adapters located at the ends of the extension cables that connect to the current generator.
Some manufactures provide supplementary extension pins that reach beyond the insulating protective shrouds to insert into an extension cable adapter. However, although the connectors themselves still remain shrouded, the pin extensions are now exposed, and reintroduce the possibility of unintended electrical contact between the pins causing a short circuit or with the patient. The extension pins also can be readily disengaged from the medical device extension cable adapter even during patient treatment and with a pulling force less than the minimum mandated by federal regulations.
To meet the regulatory requirements, medical device extension cable adapters have been modified to receive shrouded connectors without the need for additional extension pins. A locking attachment such as that used in the ADAP-2000/PACE-LOC™ system (Remington Medical, inc, Alpharetta, Ga.) ensures that the shrouded connectors cannot disengage the adapter without removing the lock and applying significant force. These connection locking systems, however, are expensive and complex to manufacture.
There is still a need, therefore, for a means of electrically connecting wire electrodes to a medical device that does not require an intervening cable adapter. There is also a need to prevent uninsulated and conductive regions of the wire electrodes that enter the patient from self-contacting and short circuiting or injuring the patient by directly contacting the skin rather than delivering the current to the intended target organ.